1. Field of the Invention
The present invention relates to a storage device system for a computer system.
2. Description of the Related Art
Technology for the storage of the content of a file stored in the storage device system of a computer system at a certain point in time (referred to as a ‘snapshot technology’) is disclosed in U.S. Pat. No. 5,819,292. In this patent document, when the file is updated after a certain point in time, the content of the file prior to update are retained without being deleted to realize the snapshot technology.
According to U.S. Pat. No. 5,819,292, when a snapshot is created, a snapshot is created for all files stored in the storage device system. The problem of conventional technology is that, even when the storage device system includes files for which a snapshot is not required since a snapshot is created for all files in the storage device system, disk capacity is required to store a snapshot for all files, increasing the cost of the storage device system.
A storage device system having snapshot technology for efficiently using the storage device system, and reducing the cost of the storage device system, is therefore disclosed.